Mineral oil compositions and additives therefor



United States Patent 3,189,546 .BHNERAL 0111, OJMPBSKTHONS AND ADHEEITPJES THEREFGR Henricus G. E. van der Voort, Amsterdam, Netherlands, assignor to Shell Gil Company, New York, N.Y., a corporation of Delaware No Drawing. Filed Dec. 3, 1969, Ser. No. 74,469 Claims priority, application Netherlands, Feb. 9, 1969, 245%,216 3 Ellaims. (Cl. 252-47) This invention relates to improved lubricating oil composition and to oil-soluble additives therefor having improved detergent and wear-inhibiting properties.

Combustion engines, such as gasoline engines and diesel engines, are more or less subject to Wear of cylinders, pistons and piston rings, In automobile engines, in particular, it is a known phenomenon that considerably increased wear occurs when the cylinder temperature remains rela tively low, as is the case when driving short distances. According to the general view this is due to moisture condensing on the cool cylinder walls in the presence of acids, such as sulfuric acid from sulfurous fuel, hydrochloric acids from lead scavengers, and organic acids from incompletely burnt gasoline. The corrosion caused by these acids, also termed cold corrosion, is responsible for much of the piston and cylinder wear in automobiles.

in order to inhibit Wear in combustion engines, it has already :been proposed to incorporate in the lubricating oil certain additives capable of rendering the said acids harmless by neutralizing them. Examples are oil-soluble neutral or basic organic metal compounds, such as calcium, barium or zinc salts of petroleum sulionic acids, of alkylated hydroxy benzoic acids, and others. in .any cases it has been possible to obtain good results by incorporat-ing such organic metal salts in the lubricating oil. The use of metal salts, however, is attended by drawbacks. ne disadvantage, for example, is the fact that the metal salts formed by neutralization of the acids resulting from the combustion are generally insoluble in oil. This may lead to disturbances, particularly as a result of the formation of deposits in the combustion space which may subsequently cause precombustion.

It has now been found that excel-lent detergent and wear inhibitors for lubricants are provided by reacting (I) polymerized 1,2-allrylene imines with (11). a nonpolymerizable oil-soluble polar-containing compound selected from the group consisting of (Ila) epoxy or thicet-hoxy compounds having an oleophilic group of at least 19 carbon atoms, preferably a C1040 alkyl radical in the molecule or (1117) a hydroxy aromatic compound containing an cleophilic C preferably C1448 alkyl radical in the molecule.

The polymerized imines are derived'from 1,2-alkylene.

imines having the formula V in which R is H or an alkyl radical.

The polymerized 1,2-alkylene irnines (l) are preferably US. Patent 2,318,730 or by thermal decarboxylation of 2-0xazolidones. The resultant products generally consist il l fidb Fatented June 15, 1965 ice of mixtures of polymerization products of varying degrees of polymerization and may contain either branched-chain or straight-chain molecules Although-polymerized 1,2- alkylene imines of any degree of polymerization may be used, products having an average degree of polymerization greater than 5, particularly between 15 and 25, are preferred. The molecular weight of the polyalkylene imines is within the range such that it has an intrinsic viscosity of about 0.025 to about 3 when measured in isopropanol at C. It is necessary for the polyalkylene imines employed to be soluble in oil. Polyalkylene imines are available commercially as -70% water solutions and such a product is Badische An lin und Soda Fabr-iks Polymin P, which is a to 70% water solution of polyethylene imine. A preferable Polymin P (A) is one containing about 47% by Weight of polyethylene imines, about 53% by weight Water and 4.76 milligram atoms of basic nitrogen per gram.

Suitable organic compounds (Ila) or (11b) which are reacted with polymerized 1,2-allrylene imines to oil-soluble products are as'stated (Ila) compounds containing an oleophilic group (alkyl group) having at least 10 carbon atoms and an oxirane ring or its thio counterpart. Examples of such compounds include epoxy allcanes such as epoxy dodecane, epoxy tridecane, epoxy tetradecane, epoxy pen-tadecane, epoxy hexadecane and the like. Particularly suitable are the epoxy allranes which may be obtained by epoxidiation of olefins having from 14 to 18 carbon atoms. Other examples of suitable epoxy compounds are: (Ha esters of an aliphatic carboxylic acid having 1030 carbon atoms preferably 12-18 carbon atoms and an epoxy alcohol, particularly esters of an aliphatic carboxylic acid and glycidol, such as glycidyl laurate, glyciclyl stearate, thioglycidyl laurate or (lla ethers containing an epoxy ring, such as epoxy aryl others in which the aryl group carries an alkyl group with at least 8 carbon atoms, especially glycidyl-alkyl phenyl others, such as glycidyl-C -C alkylphenyl ether. Use may also be made of epoxy or thioepoxy alkyl alkyl ethers, for instance tglycidyl-alkyl ethers such as glycidyl-lauryl ether or glycidyl stearyl ether, thioglycidyl lauryl ether, glycidyl ether of C alkyl phenol.

Suitable organic compounds (111;) are compounds containing a phenolic hydroxyl group, preferably alkyl phenols, par.lcularly C ,C alkyl phenols, e.g., tetra-- decyl, hexadecyl, octadecyl phenols, as well as C cracked wax olefin phenols.

According to the invention the polymerization products of LZ-alkylene imines are converted with the organic compounds (H) by contacting the components, preferably in i the liquid phase; in a homogeneous medium. The polymerized 1,2-allcylene imine is generally employed as .a solution in an organic solvent, which if desired, may also contain water. Suitable solvents are in particular alcohols having trom l to 10 carbon atoms, e.g. methanol, ethanol,

' isopropanol, the butanols, pentanols, and the higher alcohols, for example is'ooctanol and isononanol and ether alcohols, such as butyl carbitol, and also mixtures of these alcohols with water and/or hydrocarbom'for example gasoline fractions or beuzenoid hydrocarbons. The organic compounds (ll) are added as such to the solution.

pressure and oiliness agents oil,.for example a mineral lubricating oilfraction or" low viscosity, before the. solvents-are removed so'that after the removal of the solvents a concentrate is obtained which is suitable for addition as such to a lubricating oil. No operations such as centrifuging or fiitering are required. All that is required to obtain a product which is. clear'and entirely soluble in lubricating movalof the solventsby distillation. V

Thereaction is generally carried out at temperatures in the range of from 20 C. to 130 C,, although'higher orlower temperatures are also possible. Thereact'ants are generaily reacted in such quantities that an excess of polymerized 1,3-alkylene imine isused per gramequivalent of the organic compound, viz.. more'than 1 gram-atom of nitrogen peroxirane ring when use is. made of a compound containing anoxirane ring, or per double bond when use is made of a compound containing a double bond activated .by an esten'fied carboxyl group, or per hydroxyl group when .a compound containing a phenolic hydroxyl group is employed. The excess may be, for example, 25 to 160%, but theuse, of an equivalent.

oil is the re- 'or smaller quantity of polyalkylene irnine is not excluded.

The products obtained according to the inventionare suitable as additives to lubricatingoils of various types. Such mineral lubricating oils are of diverse Viscosity range 'frohrSAE 5W viscosity grade, to SAE 140 grade and a-rederived from paraflinic, naphthenic or asphaltic base crudes... Representative oils are refined high viscosity index mineral-oils having a viscosity of 100 F; of 100 to 250 SUS. A typical mineral lubricating oil (X) of this type had the following properties:

Gr. API, 60/60 F.

Viscosity index (Dean and Davis) 93 Viscosity, SUS at 1Q0 F -4 103 The additives of this invention are also suitable incorweight of Water and 4.76 milligram-atoms of basic nitrogen per gram) from which the water had been removed after addition of ethanol and benzene by azeotropic distillation. A quantity of 19.97*pa'rts by weight of the water-free product containing an overall quantity of 199.7 milligram-atoms of basic nitrogen was dissolved in 120 parts by weight of a 1:1 ethanolbenzene mixture. A quantity. of 31.2 parts by weight of epoxy dodecane (prepared by epoxidizing dodecene-1)-was added to this solution; 'The mixture contained 0.85 gram-atom .of epoxy-oxygen per" gram atom of basic nitrogen. The

mixture was then boiled under reflux over a steam bath.

for 20 hours. 'Aquantity of 213.3 parts by weight of an extracted Venezuelan parafiinic lubricating oil having a viscosity of 24 cs. at 150 F., was subsequently added, after which the solvents were removedby distillation with heated steamof 1305C. A quantity of 263.5 parts by weight of concentrateirl the said oilwas obtained which contained 19% by weight of conversion product' and in' which per'grarn 0.85 milliequivalent of present. 7 V v 7 EXAMPLE II 7 The starting material was 'the'glycidyl ester prepared basic'nitrogen was from a mixture of C 5C branched aliphatic carboxylic acids obtained from (E -C oletins by adding thereto by.

means of an addition reaction carbon monoxide and water in the presence of boron trilluoride and phosphoric acid equivalent of basic The. quantity of the products of the invention incorporated into lubricants may vary within wide limits. In generalthe desired improvement is already obtained when the quantity incorporated varies between 0.05 and 5%, particularly between 0.1 and. 1%, based on the finished lubricant. Inv special cases, however, quantities even greater than the said quantities may be added, for example in the case of diesel engines in which use is'made of fuel having a high sulfur content.

In their use the present products may also be combined with ,other additives, such as anti-oxidants, detergent dopes, viscosity-index improvers, corrosion inhibitors,

. Polymin P (approximately 53% .by weight of water), was diluted with 700 parts by weight of isopro panol. A quantity of 300 parts by weight of the said glycidyl 'ether was added to this solution of PolyminP containinglll) milliequivalents of basic nitrogen. The resultant mixture containingper gram-atom of basic nitrogen 0.625 grarnatom of epoxy-oxygen was boiled'with, stirring'for half 1 an hour. The solvents were then removed by distillation under reduced pressure, a quantity. of 861.7 'parts by' weight of an extracted parafiinicimineral lubricatin g oil. having'a viscosity off24 cs. at 190? F. being sirnultane-.

anti-foaming agents, pour-point depressants, f extrerneandother materials generally added to lubricants.

EXAMPLES By'basic nitrogen in the following examples is meant the 'base'which can be titrated with mineral acid. 7

YEXAMPLEI The starting material was polymerized ethylene imine Polymin P (a commercial product containing about 47% by weight of polyethylene imines, about 5 3% by as catalysts. 25.1 parts by weight of this ester (69.1 milli rams-atoms of epoxy-oxygen) were 'dissolved'in 50 parts by weight of isopropanol, after Jwhich the resultant solution was added to a'n1ixture'of.19.65 parts by weight of aqueous Polyrnin P (commercial product containing approximately 53% by weight 'of'water) and 34.5 parts by weight of isopropanol'. The resultant homogeneous mixture containing 0.75 gram-atom of epoxy oxygen per gram atom of basic nitrogen was then boiledfor 5 minutes, afterwhich a quantity'of' 51.7 parts by weight of an extracted Venezuelan :parafiinic lubricate ing oil having avis cosity 0f-24 cs. at 109 'F; was added and the solvents were removed under reducedpres'sure'; The distillation residue (86.2 parts by Weight) was a clear concentrate in the said oil, which'concent'ra'te contained:

' 39.8% by weight of'conversion product. L186 millinitrogen was present per gram of concentrate; r Y

i EXAMPLE In The sodium salt was prepared from (EH-C :alkyl' phenols obtained by alkylating phenol with a mixture'of Cit-C olefins. The glycidyl etherof C 45 alkyl phenol was prepared from the sodium salt'by means of eplchlorohydrin; A quantity of. 233.5 parts by1weight of ously added. In this way aquantity of 1277 :parts by weight of a 32.1% concentrate of the conversion product 0.953 milli-f was obtained, which concentrate contained equivalent of basic nitrogen'per gram.

EXAMPLE IV Q 377.5 parts by weight of Polymin'Pf (water content (commercialproduct) with an epoxy oxygen content of 3,50 milligram-atoms pergranr and of parts by weight of isopropanol was then added. The resultant homogeneous solution containing 0.67 gram-atom of epoxy-oxygen per gram-atom of nitrogen was boiled for half an hour. The solvents were distilled off under reduced pressure, a quantity of 1501.5 parts by weight of extracted Venezuelan parafiinic mineral lubricating oil having a viscosity of 24 cs. at 100 F. being simultaneously added. The residue (2020 parts by weight) was a 25.7% concentrate of the conversion product in the said oil and contained 0.99 milliequivalent of basic nitrogen per gram,

EXAMPLE V The starting material was C14-C1g alkyl phenol obtained by alkylating phenol with C -C olefins and distillation of the alkylation product. The alkylphenol contained per gram 3.11 mg. eq. OH. A quantity of 213 parts of weight of Polymin P (1015 mg. eq. of basic nitrogen, about 53% by weight of water) was dissolved with stirring in 1000 parts by weight of isopropanol. A quantity of 238 parts by weight of C -C alkyl phenol was added to this solution while stirring was continued. After boiling the mixture for half an hour a quantity of 518 parts by weight of the mineral oil described in the previous examples was added. The solvents were then removed by distillation under reduced pressure at a bath temperature of 95 C. A quantity of 862 parts by weight of residue containing 39.2% by weight of conversion product was obtained. The basic nitrogen content was 1.16 mg. eq. per gram.

EXAMPLE VI The starting materials were technical alkyl phenols obtained by alkylation of phenol with (E -C olefins. In the same manner as described in Example V a quantity of 1406 parts by weight of a 39.5% by weight of concentrate containing 39.5% by weight of conversion product and having a basic nitrogen content of 1.18 mg. eq. per gram was obtained from a quantity of 347 parts by weight of Polyrnin P (1650 mg. eq. of basic nitrogen, approximately 53% by weight of water). A quantity of 390 parts by weight of technical alkyl phenol (2.09 mg. eq. of OH per gram) and 849 parts by weight of the mineral lubricaing oil referred to in the previous examples in 1000 parts by weight of isopropanol as solvent.

In order to demonstrate the utility and improved properties of compositions of the present invention the compositions identified inTables I, II and HI were tested for the oxidation stability and extreme pressure and antiwear properties under the following conditions.

Engine tests The engine tests were carried out in a C.R.F. gasoline engine to determine the anti-wear properties, in a Potter gasoline engine to determine the anti-sludge properties, and in a Caterpillar diesel engine to determine the detergent properties.

C.F.R. gasoline engine Water-cooled single-cylinder, four-stroke engine. The test lasted 45 hours. The fuel was a gasoline having a sulfur content of 0.06% by Weight and contained 0.7 ml. TEL per US. gallon. Cylinder cooling water temperature was 40 C.

Patter gasoline engine Water-cooled singlecylinder, four-stroke engine. The test lasted 28 hours. The fuel was a motor gasoline having 1.5 ml. TEL per US. gallon and a sulfur content of 0.07% by weight. The cylinder cooling water temperature was about 500 C.

Caterpillar Water-cooled single-cylinder, four-stroke engine, The test lasted 48 hours. The fuel was a gas oil having a sulfur content of 0.9% by weight. The cooling water temperature was about 80 C. The engine power was 18 H.P.; bore 5%; stroke 8"; swept volume 3.4 liters.

The products according to the invention were all tested in the form of solutions in an extracted Venezuelan paraffinic mineral lubricating oil having a viscosity of 114 cs. at 100 F., which lubricating oil in most cases also contained an ash-free lubricating oil additive having detergent properties. The additives according to the invention were added in the form of a concentrate to the mineral lubricating oil and these concentrates had been added according to the examples. The tests are assembled in the following Tables L111. Table I shows the anti-wear properties imparted by the products according to the invention to the mineral lubricating oil. Table H shows the anti sludge properties and Table III shows the detergent pro erties imparted to the lubricating oil.

TABLE I.C.F.R. WEAR TESTS Percent Ash-tree addireduction Additive of the invention tive* with in piston (concentrate) detergent ring wear eiiect compared to undoped oil 1.18% by weight of additive of Ex- 2% by weight; 65

amp e 0.86% by weight of additive of Ex- None 70 ample V.

Do 1.7% by weight 73 None 2% by weight--- a 0 *Copoly'mer of stearyl methacrylate/lauryl methacrylate/hydroxyethyl methacrylatc (5:5:2)

TABLE II.PETTER SL'UDGE TESTS TABLE III.GATERPILLAR PISTON FOULING TESTS Ash-iree additive* Piston Additive of the invention (concentrate) with detergent fouling (l0 efiect is clean) 0.93%I'rg weight of additive of Exam- 1.7% by weight-.- 8. 8

pie 0.86% by weight of additive of Examdo 9:2

ple V. V Nnn do 7. 8 Dn None 4. 5

*See footnote, Table I.

Additional improvements with respect to oxidation stability and scufiing inhibition can be imparted to the oil composition of this invention by incorporating small amounts (0.01%2%, preferably 0.1%1%) of bisphenolic antioxidants such as p,p-methylene bisphenols such as 4,4'-methylene bis(2,6-ditert-butyl phenol) or arylamines such as phenyl-alpha-naphthylamine and mixtures thereof. Anti-scuffing agents include organic phosphites, phosphates, phosphonates and their thio-derivatives, such as C alkyl phosphites, or phosphonates, e.g., diand tributyl, octyl, lauryl, stearyl, cyclohexyl, benzyl, cresyl, phenyl, phosphites or phosphates, as well as their thioderivatives, P S -terpent reaction products, e.g., P S -pine oil reaction product and alkali metal salts thereof such as a potassium salt of a P S -terpene reaction product, phosphonates such as dibutyl methanephosphonate dibutyl trichloromethanephosphonate, dibutyl monochloroand the like.

methanephosphonate', dibutyy chlorobenzenephosphonate, The fullesters of pentavalent phosphorus acids such as triphenyl, tricresyl, trilauryl and tristearyl ortho-phosphates or potassium salt of P S -terpene reaction product are preferred.

I claim as my inventioni 1. An improved mineral lubricating oil composition comprising a major amount of mineral lubricating oil and a minor amount, sutficient to inhibitwear, of'an oil-soluble reaction product obtained by reacting at between 20 C. and 130 C. a polymerized 1,2-alkylene imine having 'an intrinsic viscosity of fnom about 0.025 to about 3 in isopropanol at 25 f C. with an oil-soluble polar-containing compound selected from the groupconsisting of C 4 epoxy-alkane, C1448 thio-epoxy' alkane, esters, of glycidol and alkanoic acids-having from10 to 30 carbon' atoms, glycidy1 ethers of' an alcoholselected from the group consisting of alkyl phenol andalkanol each having from 14 to 18 carbon atoms and C1443 alkyl phenols the imine being present in the amount of 1.25 to 2gramequivalents per gram-equivalent of the oil-soluble polarcontaining compound. a. .2. Animprovedmineral lubricating .oil composition comprising a major amount of mineral lubricating oil and from about 0.5% to about 5% by weight of anoil-soluble reaction product'obtained :by reacting at between 20 C.

and 130 C. a polymerized 1,2-alkylene-imine having an intrinsic viscosity of from about 0102510 about 3in' isopropanol at 25 C. with an oil-soluble epoxy alkane having from 14 to 18 carbon atoms in the molecule the imine being present in the amount of 1.25-2 gram-equivalents per gram-equivalent of the oil-soluble polar containing compound.

3. An improved mineral lubricating oil composition comprising a major amount of mineral lubricating oil and from about 0.5 to about 5 %'by weight of an oil-s01 uble reaction product obtained by reacting at between 20 C. and 130 C. apolymerized 1,2-alkylenei mine' hav-' ing an intrinsic viscosity of from. about 0.025 to about 3 in isopropa'nolat 25C. with an oil-soluble ester .of an falkanoic acid having from 10 to 30 carbon atoms in the molecule and. glycidol the iminebeing present in the amount of 1.25-2 gram-equivalents per-gram-equivalent of the oil-soluble polar-containing compound.

4. An improved mineral lubricating oil composition comprising a major amount of mineral lubricating oil and from about 0.5 to about 5% by weight of an oilsoluble reaction product obtained by reacting at between 20 C. and 130 C. a polymerized '1,2-'alkylene imine having an intrinsic viscosity of from about 0.025 to about 3 in isopropanol at 25 C. with an oil-soluble glycidyl ether of (3,44 alkyl phenol, the imine being present in the amount of 125-2 gram-equivalents per gram-equivalent of the glycidyl ether compound.

' 5. An improved mineral-lubricating oil composition and from about 0.5 to about 5%. by weight of a reaction productobtained by reacting at between 20 .C. and 130 C, a polymerized ethylene 'irnine having an. intrinsic viscosity of from about 0.025 to about 3 in-isopropanol at 25 C. and glycidyl ester of C -C1 aliphatic carboxylic acid the imine being present in the amount of 1.25-2 gram-equivalents .per gram-equivalent of. C1448 aliphatic carboxylic acid. p V

7. An improved mineral: lubricating oil composition comprising a major amount of mineral lubricating oil and from about 0.5 to about 5% by weight. of a reaction product obtained by reacting at'between 20C.. and 130 C. a polymerized ethylene imine having an intrinsic viscosity of from about 0.025 to about 3 in isopropanol at 25 C. and glycidyl decyl ether theimine being present 'in the amount of 1.25-2 gram-equivalents per' gramequivalent of glycidyl decylether. V

8. An improved mineral lubricating oil composition comprising a major amount of mineral lubricating oil and from about 0.5 to about 5% by weight of a reaction product'obtained by reacting at between 20 C. and 130 C. a polymerized ethylene imine having an intrinsic vis-' cosity of from about'0.025 to about '3 in isopropanol at 25 C, and C 4 alkyl phenol the'imine being. present in the amountof 1.25-2gram-equivalents per gram-equivalent of C1448 alkyl phenol.

References Cited by the Examiner UNITEDgSTATES PATENTS DANIEL E. wYMAN, Primary Examiner.

JULIUS GREENWALD, Examiner. 

1. AN IMPROVED MINERAL LUBRICATING OIL COMPOSITION COMPRISING A MAJOR AMOUNT OF MINERAL LUBIRCATING OIL AND A MINOR AMOUNT, SUFFICIENT TO INHIBIT WEAR, OF AN OIL-SOLUBLE REACTION PRODUCT OBTAINED BY REACTING AT BETWEEN 20* C. AND 130*C. A POLYMERIZED 1,2-ALKYLENE IMINE HAVING AN INTRINSIC VISCOSITY OF FROM ABOUT 0.025 TO ABOUT 3 IN ISOPROPANOL AT 25*C. WITH AN OIL-SOLUBLE POLAR-CONTAINING COMPOUND SELECTED FROM THE GROUP CONSISTING OF C14-18 EPOXY-ALKANE, C14-18 THIO-EPOXY ALKANE, ESTERS OF GLYCIDOL AND ALKANOIC ACIDS HAVING FROM 10 TO 30 CARBON ATOMS, GLYCIDYL ETHERS OF AN ALCOHOL SELECTED FROM THE GROUP CONSISTING OF ALKYL PHENOL AND ALKANOL EACH HAVING FROM 14 TO 18 CARBON ATOMS AND C14-18 ALKYL PHENOLS, THE IMINE BEING PRESENT IN THE AMOUNT OF 1.25 TO 2 GRAMEQUIVALENTS PER GRAM-EQUIVALENT OF THE OIL-SOLUBLE POLARCONTAINING COMPOUND. 